Installing the Titan on a Kossel Mini

The T3P3 Kossel mini is a delta design built with belt drives, NEMA17 motors, David Crockers firmware, IR probe and on my machine, the PanelDue display.

My machine has some modifcations from the original design include a side-mounted spool holder, some cosmetic in-fill strips to hide some of the wiring in the aluminum struts, and LED lighting on the top frame from IKEA.

The installation of the Titan is one of the largest changes from the orginal design I’m doing, and the first change that alters the mechanical characteristics of the machine.

The first thing I needed to do was print a bracket to mount the titan to the printer – I could have just bought this with the extruder, but instead elected to 3D print it using the design on Thingiverse – which will give me more flexibility if I need to alter it to fit the Kossel frame.

It then turned out that the bolts I was using were too long – so a quick trip to the hardware store later and I had some washers to pad things with…  the end result is the Titan mounted to the top frame of the printer.

Wiring was fairly simple – I just had to remove the print bed to access the electronics, connect the wires instead of the current extruder wiring, and route the cable up the frame of the printer so it wouldn’t foul any of the moving parts.

Before re-installing the print bed, I did a quick extrusion test to ensure the direction was correct

With no filament loaded, send this g-code to override the cold extrusion protection.  Doing this with filament loaded can damage your printer.

M302 P1

Running an extruder test with G1 E300 F300 it quickly became obvious that this extruder runs in the reverse direction to my previous one.

This can be fixed by reversing the motor definition in the config.g file (on DC42 firmware anywhere) – find the line that reads:

M569 P3 S1                ; Drive 3 goes forwards

and change it to

M569 P3 S0                ; Drive 3 (extruder) goes in reverse

All that was left to do was set the extruder steps to 456 (as per the instructions from E3D) and perform an extruder calibration test to make sure it actually moved 100mm of filament when asked.

Extruding 100mm of filament is done with

g1 e100 f100

As always, the instructions from E3D cover how to check this and tweak the value.

Mine came out at 114mm of filament when asked to extrude 100, so I had to tweak the value to

456 * (100/114) = 400

Retesting the 100mm extrusion confirmed that was correct confirmed that 400 was correct.

Finally, I trimmed the bowden tube to length and installing it into the end of the E3D v6 hotend, tidied up the wiring, reinstalled the print bed and ran a print test before removing the old extruder (however the bracket remains as a usual point for wiring to be attached)


Useful Links:

E3D Titan bracket on Thingiverse
E3D Titan Assembly Guide

Other articles in this series:

  1. Introduction
  2. Unboxing and Assembly
  3. Physical Installation and calibration on the T3P3 delta (this post)
  4. Final thoughts